With spring training less than a month away, the Mariners have finalized their player development staff for the 2020 season.

General manager Jerry Dipoto and Andy McKay, Seattle’s director of player development, announced the coordinating staff as well as the coaching staff for each of the club’s seven affiliates, Tuesday.

The most notable internal promotion was given to Tony Arnerich, who will move from catching coordinator to minor league field coordinator. Arnerich, who will be entering his fourth season in the organization, fills the opening created when Carson Vitale was promoted to the Major League coaching staff.

“(Tony Arnerich) is a well-rounded leader who has earned the respect of those in player development as well as our other baseball operations departments,” McKay said in a news release. “He has been a steady voice of advocacy for our initiatives and his relationship with Carson Vitale will be critical in creating seamless transitions for our players between our major league and minor league groups.”

The remainder of the eight-person coordinator staff were all with the Mariners last season. Mike Cameron, who was a part-time special assistant last season, will be in a full-time role this season, working largely with the outfielders. Alvin Davis (10th season), Pete Harnisch (5th season), Dan Wilson (7th season)  also return as special assistants. Hitting coordinator Hugh Quattlebaum, Latin American field coordinator Cesar Nicolas and pitching coordinator Max Weiner all return for a second season.

The minor league affiliates will have a fair amount of continuity from last season and seasons prior at the managerial position.


At Triple-A Tacoma, longtime Rainiers manager Daren Brown is back for his ninth season. After serving as manager for the Rainiers from 2007-2013, Brown returned to Tacoma last season. He is the winningest manager in Rainiers history, posting a 494-508 record over 1,002 games. This will be his 23rd season in the Mariners organization.

Hitting coach Roy Howell, who has worked with Brown the last five seasons at multiple levels, is back with the Rainiers, while Rob Marcello was promoted from High-A Modesto to serve as Tacoma’s pitching coach. It will be his second season in the Mariners’ system.

After losing manager Mitch Canham to Oregon State during the middle of last season and having Nicolas serve as the interim manager, Double-A Arkansas will have Dave Berg as manager in 2020. Berg spent last season as the manager of Low-A West Virginia. This will be Berg’s fifth season with Seattle. He also worked as a coordinator and as Tacoma’s hitting coach in 2018.

Pitching coach Alon Leichman, who worked with Berg in West Virginia last season, was also promoted to Arkansas while hitting coach Joe Thurston moves up from Short A-Everett.

The Modesto Nuts will have Denny Hocking as their manager for a second straight season. This is Hocking’s fourth season in the system. He also had a stint as Low-A Clinton’s manager in 2018 and as Tacoma’s hitting coach in 2017.

Seattle hired Sean McGrath to serve as pitching coach for the Nuts this season. He spent the last two season at Elon University in the same role. That past experience will be useful since the Mariners’ first-round pick in 2019, right-handed pitcher George Kirby, will front the Nuts’ rotation to start the season. Reliever Ty Adcock, the Mariners’ eighth-round pick in 2019, also pitched for McGrath at Elon and is expected to be in Modesto’s bullpen.


Modesto’s hitting coach will be a name familiar to Mariners fans and folks in the Tri-Cities. Former utility infielder Shawn O’Malley, who spent parts of two seasons in the organization and was a standout for Southridge High, has been hired to serve as hitting coach. It will be O’Malley’s first year as a coach.

With Berg promoted, Low-A West Virginia will have Eric Farris as its manager in 2020. Farris was the Power’s hitting coach in 2019. This is his third season in the system, having worked as hitting coach in Everett in 2018. Joining Farris will be pitching coach Nathan Bannister and hitting coach Rob Benjamin. A farmhand in Seattle’s system for two seasons after being taken in the 28th round of the 2016 draft, Bannister is making his coaching debut. Benjamin spent 2019 as the hitting coach for the Mariners’ Dominican Summer League team.

After holding a unique role as a player/coach for Modesto and then taking over as interim manager in Everrett on July 23 after Jose Moreno was fired by the organization, Louis Boyd returns to the Aqua Sox as the full-time manager. Ari Ronick will return as pitching coach while Michael Fransoso will make his coaching debut as hitting coach.

In one of the system’s longest runs in the same role, Zac Livingston is back as manager for the Arizona Rookie League Mariners for the fifth straight seasons. The AZL Mariners have made the postseason the last two years. Yoel Monzon will return as pitching coach while Jose Umbria will work as hitting coach after spending last season in Modesto in the same role.

Down at the Mariners’ academy in the Dominican Republic, Austin Knight is back for a fourth season as manager. His staff includes pitching coach Jose Amancio, hitting coach Brett Schneider (first year) and coaches Luis Caballero (first year) and Guady Jabalera (first year). Luis Matias enters his 3rd season as Assistant of Baseball Operations (DR).



Hitting CoachPitching Coach



Triple-A Tacoma

Daren BrownRoy HowellRob Marcello

Double-A Arkansas

Dave Berg

Joe Thurston

Alon Leichman

High-A Modesto

Denny Hocking

Shawn O’Malley*

Sean McGrath*

Low-A West Virginia

Eric FarrisRob Benjamin

Nathan Bannister*

Short-A Everett

Louis BoydMike Fransoso*

Ari Ronick

Rookie Peoria

Zac LivingstonJose Umbria

Yoel Monzon

Dominican MarinersAustin KnightBrett Schneider*

Jose Amancio

Guady Jabalera*

Luis Caballero

* = 1st-Year with Mariners organization